Manufacture of fabrics from natural fibers involves several complicated processes for processing the natural fibers into yarns which are then woven into fabrics. Although the processes differ for different fibers, such as wool or cotton, there are certain common features if the natural fibers are short. The fibers may be used for a yarn if they have surfaces that will cohere to each other thus permitting the fibers to adhere to each other. The process of producing yarn may from these fibers be thought of as beginning with carding. The carding process takes a large mass of the short natural fibers which are scattered in essentially a random manner and disentangles the fibers and arranges them in a more ordered and parallel arrangement. If the fiber is cotton, numbers of now somewhat parallel fibers are brought together to form what is known as a sliver after having been carded. The slivers, however, contain fibers that are still not arranged in a parallel fashion as well as fibers that are too short to form the high quality yarn needed for good fabrics. To remove the short or waste fibers and to make the fibers more nearly parallel, the sliver is passed through pairs of drafting rollers. Each successive pair of drafting rollers rotates more rapidly than the previous pair. As a result, the fibers are drawn out with respect to each other and become more nearly parallel and the shortest fibers drop out.
The slivers are then wound upon bobbins. The bobbin is typically cylindrical in shape with a central bore through its length enabling it to be placed on a spindle. After the drafting process, the fibers such as cotton or wool, are typically put through another process known as spinning in which the fibers are again drawn out, a twist given to the fibers to give them strength, and then they are again wound on a bobbin. The final product of the spinning process is a yarn from which the desired fabric is woven.
It is generally desirable to remove the very short fibers so they will not be present in the final yarn since yarns using only long fibers are stronger and produce finer fabrics than yarns that also use short fibers. Some of the short fibers or waste slivers are removed during each stage. However, not all of the waste fibers are removed in the spinning or the drafting process and some waste fibers will be wound upon the bobbins in each stage and left there after the other fibers have been unwound from the bobbin. To maintain the high quality of these finished product, these waste fibers or slivers must be removed from the bobbin before the bobbin is used again to eliminate the possibility that the waste slivers will form part of the finished yarn and degrade its quality. After removal from the bobbins, the waste slivers should be collected in suitable storage units. This prevents the slivers from again being picked up by the bobbins and also minimizes the inhalation of slivers by textile workers in the factory, which constitutes a health hazard.